Biological Level Of Analysis
How does or physiology and genetics
effect our behavior?
Development of Biological Perspective
• 370 BC….Hippocrates and his 4 Humors
Two things really catapulted us to
think that biology effected behavior…
1848
Phineas Gage
1859
Charles Darwin wrote “On the Origin of
Species”
• Idea that all species
developed over time with
the idea that “behavior is
adaptive”.
Principles of BLA
Outline the principles that define the
biological level of analysis
and how they are demonstrated in research
1. emotions and behavior are products of
anatomy and physiology and endocrine
systems
2. patterns of behavior can be inherited
3. animal research can help us understand
behavior
1. Emotions and behavior are products
of anatomy and physiology and
endocrine systems
Links have been found
between psychological
events and physiological
activities in 3 main
areas
• The effect of
neurotransmitters
• The effect of hormones
• The effect of brain
localization
Research Example
Oxytocin
Oxytocin
• Hormone produced by
pituitary gland.
• Produced by all
mammals but linked
more to woman.
• Called the “love
hormone” in the media
but should maybe be
called the “morality
hormone”
Oxytocin
• Holt discovered in 2008
that physical contact
increased oxytocin
levels.
• Morhenn et al. (2008)
• Adam Smith “A Theory
of Moral Sentiments”
• The Pigeon Drop Con
2. Patterns of behavior can be
inherited
Based on work of Darwin
• Genetics
• Evolutionary Psychology
Traits are passed on from generation to generation.
Especially those that help ensure our survival.
Research Example
Homosexuality
Homosexuality
Bailey and Pillard (1991)
• Studying the rates of
homosexuality between
monozygotic (MZ) and
dizygotic (DZ) twins.
But is homosexuality
adaptive?
Zietsch et al. (2008)
• 4904 identical twins
3. Animal research may inform our
understanding of behavior
• Based on Darwin’s idea
of evolution we share a
common ancestry with
animals.
• So in some ways we are
fundamentally the
same.
• Examples…..
Critical Periods
Imprinting
• the optimal period
shortly after birth when • The process by which
certain animals form
an organism’s exposure
attachments during a
to certain stimuli or
critical period very early
experiences produce
in life.
proper development.
Harry Harlow and his Monkeys
• Discovered that
monkeys preferred the
soft body contact of a
cloth mother, over the
nourishment of a
hard/wirily mother.
Rats and an enriched environment
• Rats raised for a period
of time in an
impoverished versus an
enriched environment.
• What does this mean
for us?
Biological research
methods and ethics
Discuss how and why particular research methods
are used at the biological level of analysis.
Discuss ethical considerations related to research
methods in the BLA.
1. Laboratory Experiments
2. Case Studies
3. Correlational Studies
Laboratory Experiments
• Trying to show cause and
effect relationships.
• Often times these types
of experiments can be
unethical using
humans…why?
• Humans are also more
prone to the placebo
effect.
• Thus we more often use
animals.
Case Studies
• Instead of causing
change in a human….we
take advantage of a
naturally occurring
irregularity.
• No harm done because
we are describing what
has already happened.
• Maybe a threat to
anonymity.
Correlational Studies
• No real manipulation of
variables so does not
really show what?
• The most common type
of studies done today.
• Twin research
• Brain imaging research.
Physiology and behavior:
Localization of function
• Explain one study related to localization of
function in the brain.
• Examine one interaction between cognition
and physiology in terms of behavior
(Evaluate two relevant studies).
Early investigation of localization of
function
• Phrenology